Restoring stdin and stderr (in a logging function)

[s243a]

In a log function, I have I restored stdin and stderr as follows:

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exec 6>&1           # Link file descriptor #6 with stdout.
exec &> >(tee -a "$LOGFILE")
....
exec 1>&6  
exec 6>&-      # Restore stdout and close file descriptor #6.
exec &2> /dev/stderr   

https://gitlab.com/s243a/psandbox/-/blo ... box.sh#L90

I'm looking for coding suggestions here. One thing that I think might be a good idea is if for some reason "6" ends up being a bad file descriptor I should do a fallback like:

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exec 1> /dev/stdin
or
exec 1> /dev/console

I also saw the following suggestion:

0

If the program runs on a Linux environment, you can freopen ("/dev/stdout", "a", stdout).

But if you know that stdout was the terminal, freopen ("/dev/tty", "a", stdout) or the equivalent for other OSs—even Windows.

https://stackoverflow.com/questions/110 ... o-terminal

also what is the difference between:

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exec 1>&6  

and

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exec &1>&6  

I think that they will both work.

[jamesbond]

Re: your last question, the answer is: they are the same for bash.
For other shells, only the first form will work. So beware.